# ---
# title: 1598. Crawler Log Folder
# id: problem1598
# author: Indigo
# date: 2021-06-01
# difficulty: Easy
# categories: Stack
# link: <https://leetcode.com/problems/crawler-log-folder/description/>
# hidden: true
# ---
# 
# The Leetcode file system keeps a log each time some user performs a _change
# folder_ operation.
# 
# The operations are described below:
# 
#   * `"../"` : Move to the parent folder of the current folder. (If you are already in the main folder, **remain in the same folder** ).
#   * `"./"` : Remain in the same folder.
#   * `"x/"` : Move to the child folder named `x` (This folder is **guaranteed to always exist** ).
# 
# You are given a list of strings `logs` where `logs[i]` is the operation
# performed by the user at the `ith` step.
# 
# The file system starts in the main folder, then the operations in `logs` are
# performed.
# 
# Return _the minimum number of operations needed to go back to the main folder
# after the change folder operations._
# 
# 
# 
# **Example 1:**
# 
# ![](https://assets.leetcode.com/uploads/2020/09/09/sample_11_1957.png)
# 
#     
#     
#     Input: logs = ["d1/","d2/","../","d21/","./"]
#     Output: 2
#     Explanation: Use this change folder operation "../" 2 times and go back to the main folder.
#     
# 
# **Example 2:**
# 
# ![](https://assets.leetcode.com/uploads/2020/09/09/sample_22_1957.png)
# 
#     
#     
#     Input: logs = ["d1/","d2/","./","d3/","../","d31/"]
#     Output: 3
#     
# 
# **Example 3:**
# 
#     
#     
#     Input: logs = ["d1/","../","../","../"]
#     Output: 0
#     
# 
# 
# 
# **Constraints:**
# 
#   * `1 <= logs.length <= 103`
#   * `2 <= logs[i].length <= 10`
#   * `logs[i]` contains lowercase English letters, digits, `'.'`, and `'/'`.
#   * `logs[i]` follows the format described in the statement.
#   * Folder names consist of lowercase English letters and digits.
# 
# 
## @lc code=start
using LeetCode

function min_operations_1198(logs::Vector{String})
    res = 0
    for lg in logs
        if lg == "../"
            res = max(0, res - 1)
        elseif lg != "./"
            res += 1
        end
    end
    return res
end
## @lc code=end
